Firebox



Dec. 14, 1937. Q POLHEMUS 2,102,217

FIREBOX Filed March 26, 1956 A TTOFP/VEX Patented Dec. 14, 1937 UNITED stars ATT OFFICE FIREBOX Charles B. Polhemus, San Jose, Calif. Application March 26, 1936, Serial No. 70,969 3 Claims. (c1. 126-29) amount of fuel is required to properly heat the overlying grill area. Furthermore, combustion of the fuel is not properly promoted because of the lack of adequate channels for introducing air thereto. Again, their construction is such that the walls are readily overheated, and the process of cleaning out the ashes cannot be quickly and cleanly performed.

It is one object of the invention, therefore, to provide a firebox so constructed and arranged that a given grill area can be adequately heated with a small amount of fuel; that it permits a free and abundant flow of air to a fire built therein; in which the walls cannot become over heated; and that can be quickly and easily 7 cleaned.

It is also an object of the present invention to provide a device of the character indicated that will be economical to manufacture, simple in form and construction, that consists of few parts, that is strong and durable, and highly efi'icient in its practical application. 7

The drawing is a perspective illustration of a firebox embodying myinvention, partly in section and with parts bro-ken away.

In the particular embodiment'of the invention herein disclosed I show at i a firebox having an open top 2 over which a grill 3 is placed, and an opening 4 formed in its front end.

At 5 I show a single sheet of metal bent into the form of an M in transverse cross-section, the two side portions being indicated at 6 and i respectively, and the two walls of the V-shaped central portion being indicated at 8 and 9. This part 5 is oblong and shorter than the interior of the box' I and is supported and held in its proper shape by end pieces as Ill and l 5, these end pieces also define the ends of the chamber between walls 8 and 9 in which the fire is built.

The part 5 is also narrower than box I, being so proportioned that it may be readily passed through the opening' i. The front end piece It has an outwardly projecting flange l2 formed on its upper edge, and this flange is "mounted on a,

door l3 which functions as a closure for opening 4. Door l3 has a hook-shaped member M on its lower edge to seat on the lower edge of opening 4 and support the door i3 therein.

is subject to the heat generated in part 5, and the form of member 5 is such that the heat from most of the burning fuel is directed upon the grill area, very little of the burning fuel being buried so that its heat is indirectly used.

That the flow of air to the fuel being burned is free and ample may be seen by tracing the arrows l9 and 2B. The air flows freely over the top edges of the box I, thence downwardly between the box walls and the side portions 6 and "i of part 5, thence to and through openings l1 and IE to the pockets 2! and 22 where it is fed a into the fire through the perforations l5, H5 in walls 8 and 9. The pockets 2|, 22 are closed at both ends and consequently air entering these pockets has no outlet except through perforations i5 and I6.

The flow of air as described prevents excessive heat from penetrating to the outer walls of box I, and since there is also some movement of air between end Hi and door !3 the door handle 23 is kept reasonably cool. the part 5 is removed bodily through opening 4.

To clean out the ashes 7 It is to be understood, of course, that while I have herein shown and described but one specific embodiment of the invention, changes in form, construction, and method of assembly and operation may be made within the scope of the appended claims.

I claim:

1-. A device of the character described comprising, a firebox, a member having an M shaped transverse cross-section disposed therein spaced relation to the walls thereof and having air passages formed in its V-shaped central portion and in the bottom portions of its side portions, end plates mounted thereon and a door mounted on one of said end plates, the firebox having an opening formed in one end thereof through which the said member maybe introduced and adapted to be closed by said door.

2. A firebox member comprising, an oblong member having an M-shaped transverse crosssection, the central V-shaped portion being perforated and the side portions having air passages formed therethrough, and a closure mounted on each end of the member operative to support the several portions in rigid relation to each other.

3. A structure of the character described comprising, an open topped firebox, an oblong member that is M-shaped in transverse cross-section disposed therein and in spaced relation to the walls thereof, said member having the central V-shaped portion perforated and the side p'ortions provided with air passages to connect the spaces between the V-shaped'portion and the side portions with the spaces between the side portions and the firebox wall.

CHARLES B. POLHEMUS. 

